In 1971, Mahendra was cast by veteran director K. Balachander in the latter's film Navagraham. The film was an average grosser. Mahendra was discovered to have a nasal accent which made him funny. He acted in a variety of roles in a number of movies- particularly as a dim witted fool of a cousin- generally eclipsing roles enjoyed by Cho Ramaswamy in the 1960s and 70's.
Mahendra is also the cousin of Bollywood actress Vyjayanthimala and the co-brother of Rajinikanth and Mohanlal.